We consider the classical problem of wave stability and dispersion in a turbulent plasma background. We adopt a kinetic description for the quasi-particle turbulence. We describe an improved theoretical approach, which goes beyond the geometric optics approximation and retains the recoil effects associated with the emission and absorption of low frequency waves by nearly resonant quasi-particles. We illustrate the present approach by considering two particular examples. One is the excitation of zonal flows by drift wave turbulence or driftons. The other is the coupling between ion acoustic waves and Alfvén wave turbulence, eventually leading to saturation of Alfvén wave growth. Both examples are relevant to anomalous transport in magnetic fusion devices. Connection with previous results is established. We show that these results are recovered in the geometric optics approximation.
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